The objective of the proposed research program is to gain an understanding of the relationships which exist between the morphological, biochemical and functional components of neurogenesis. The techniques of histochemistry and quantitative microchemistry will be used to examine changes in enzymatic activity associated with carbohydrate and acetylcholine metabolism as they relate to morphological and functional differentiation of the motor neuron. Parallel studies (which will also include the metabolism of the neurologically active amino acids: glutamate, aspartate, and gamma aminobutyrate) will be made on the surrounding neural tissue. Answers will be sought to the following questions: (1) at what specific stages in neurogenesis do changes in the level of activity of enzymes associated with intermediary carbohydrate metabolism occur and are the changes observed in the motor neuron also reflected in the metabolism of the surrounding neural tissue? (2) At what specific stages of neurogenesis do changes in the level of activity of enzymes associated with acetylcholine metabolism occur? (3) What are the ontogenetic patterns for the enzymes associated with the metabolism of glutamate, aspartate, and gamma aminobutyrate in the surrounding neural tissue and are the metabolic changes of these excitatory and inhibitory amino acids reflected in the development of the motor neuron?